Update 450. Delete Node in a BST.py

Co-Authored-By: Antim-IWP <203163676+Antim-IWP@users.noreply.github.com>
Co-Authored-By: Shiwangi Srivastava <174641070+IamShiwangi@users.noreply.github.com>

Author: 3 people

Solution/450. Delete Node in a BST/450. Delete Node in a BST.py

@@ -0,0 +1,26 @@
+# Definition for a binary tree node.
+# class TreeNode:
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+class Solution:
+    def deleteNode(self, root: Optional[TreeNode], key: int) -> Optional[TreeNode]:
+        if root is None:
+            return None
+        if root.val > key:
+            root.left = self.deleteNode(root.left, key)
+            return root
+        if root.val < key:
+            root.right = self.deleteNode(root.right, key)
+            return root
+        if root.left is None:
+            return root.right
+        if root.right is None:
+            return root.left
+        node = root.right
+        while node.left:
+            node = node.left
+        node.left = root.left
+        root = root.right
+        return root